ISD1820 voice recording module

The ISD1820 Voice Recording and Playback Module is a versatile audio module designed for hobbyists, students, and engineers who want to add voice recording and playback capabilities to their electronic projects. Built around the popular ISD1820 chip from Nuvoton, this module offers natural-sounding voice reproduction , making it a reliable solution for any project requiring real human-voice output. The module comes with an integrated electret microphone , allowing the user to record audio directly without needing any additional input device. Recording duration is set to a default of 10 seconds , with sampling frequencies adjustable through external resistors for those who want to fine-tune audio quality versus recording length. Recorded messages are stored automatically and remain in memory even after power-off thanks to the chip's non-volatile storage . Playback is supported in three flexible modes: PLAYE (single-pass) , PLAYL (loop play with hold) , and jog playback for repeated triggering. All major control pins are broken out to header pins, enabling microcontroller-based control via Arduino , Raspberry Pi , ESP32 , or any 3.3V/5V logic system. An onboard 8-ohm speaker output is included for direct sound reproduction, eliminating the need for an external amplifier in most use cases. Powered by a simple 3V to 5V DC supply , the ISD1820 module is plug-and-play , beginner-friendly, and an excellent introduction to audio electronics. Specifications Main IC: ISD1820 voice recording chip Recording Duration: 10 seconds (default; adjustable via external resistor) Sampling Frequency: 3.2 kHz (default) Operating Voltage: 3V – 5V DC Onboard Microphone: Electret condenser type Speaker Output: Direct drive for 8? / 0.5W speaker Memory Type: Non-volatile (retains audio after power-off) Control Modes: REC , PLAYE (single-pass) , PLAYL (loop) , Jog playback Interface: Standard header pins for microcontroller control Module Dimensions: 54mm × 38mm Features Applications DIY Voice Recorders and personal memo devices Interactive Toys and Greeting Cards with custom voice messages Smart Doorbells and announcement systems Voice-Activated Alarms and security alerts Robotics Projects requiring spoken feedback or sound effects Educational STEM Kits teaching audio electronics and microcontrollers Arduino and Raspberry Pi voice-based applications Museum Exhibits and Kiosks with short recorded narration Accessibility Devices for users with reading or speech difficulties Industrial Notification Systems for short voice prompts Home Automation projects with audible status updates Prototyping and Hobby Projects that need quick voice integration